Diffuse-interface model for nanopatterning induced by self-sustained ion etch masking

TL;DR

This paper presents a diffuse-interface model that successfully simulates nanopatterning during ion sputtering, capturing experimental features and elucidating growth regimes and segregation effects.

Contribution

The authors develop a simple phenomenological model that reproduces complex nanopatterns and provides insights into the growth dynamics and segregation role in pattern formation.

Findings

Reproduces high-aspect ratio structures and tilted pillars in simulations.

Analyzes pillar height evolution via simulations and in situ ellipsometry.

Supports segregation as a key factor in pattern formation.

Abstract

We construct a simple phenomenological diffuse-interface model for composition-induced nanopatterning during ion sputtering of alloys. In simulations, this model reproduces without difficulties the high-aspect ratio structures and tilted pillars observed in experiments. We investigate the time evolution of the pillar height, both by simulations and by {\it in situ} ellipsometry. The analysis of the simulation results yields a good understanding of the transitions between different growth regimes and supports the role of segregation in the pattern-formation process.